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Turkish Journal of Zoology Turk J Zool (2019) 43: 536-539 http://journals.tubitak.gov.tr/zoology/ © TÜBİTAK Short Communication doi:10.3906/zoo-1904-42

Siberigondolella gen. nov., a Boreal Early lanceolate

1, 2 Ali Murat KILIÇ *, Francis HIRSCH  1 Department of Geological Engineering, Faculty of Engineering, Balıkesir University, Balıkesir, Turkey 2 Laboratory of Geology, Faculty of Sciences, Naruto University, Naruto, Japan

Received: 26.04.2019 Accepted/Published Online: 16.07.2019 Final Version: 02.09.2019

Abstract: In the Lower Triassic, at the time that segminate gondolellid defined the Tethyan regions, endemic segminiplanate gondolellid conodonts resembling the genus “” dwelled in the northern latitudes. Without the multielement apparatus characteristic of the subfamily Neogondolellinae, these forms are phylogenetically incertae sedis and one lineage was attributed to the genus Siberigondolella gen. nov.

Key words: Conodont, Early Triassic, Siberia, Siberigondolella, gondolellid

Smithian conodonts on Kotelny Island (Novosibirsk Array: Griesbachian Siberigondolella griesbachensis Islands) were reported by Klets and Yadrenkin (2001) as (Orchard); Dienerian S. mongeri (Orchard); Smithian S. exclusively segminiplanate. composita (Dagys), S. altera (Klets), S. siberica (Dagys), The presence of segminiplanate morphs in the boreal and S. jakutensis (Dagys). zone contrasts with that of the segminate genus Neospath- Range: Late Griesbachian-Smithian. odus in cherty deep waters of the Russian Far East (Buryi, Discussion: Gondolellid conodonts comprise seg- 1989; Bragin, 1991; Klets, 1998). miniplanate and segminate forms. In the Early Trias- The new genus described herein comprises the Gries- sic, segminiplanate forms were no longer present in the bachian-Dienerian Siberigondolella griesbachensis (Or- low latitudes but were dominant in high-latitude regions. chard) and Dienerian S. mongeri (Orchard), the Dieneri- Sun et al. (2012) reported that the diversity and evolu- an-Smithian S. composita (Dagys), and the Smithian S. tion of segminiplanate gondolellids appear to have closely altera (Klets), S. sibirica (Dagys), and S. jakutensis (Dagys). followed the temperature record of the time. The disap- Class Conodonta Pander, 1856 pearance of some dominant end- conodonts Order Dzik, 1976 in the late Griesbachian coincides with a temperature Superfamily Gondolelloidea Lindström, 1970 rise that began at the Permo-Triassic boundary and Family Lindström, 1970 peaked in the Late Griesbachian (Li et al., 2019). The Die- Genus Siberigondolella gen. nov. nerian cooling trend coincided with the appearance of Figures 1A–1Z several new forms. The genus Siberigondolella disappeared Generotype: Neogondolella composita Dagys, 1984; during the latest Smithian temperature peak. The late Figure 1G (from Dagys, 1984, plate XIV, fig. 5) Spathian cooling allowed the renewal of segminiplanate Derivation of the name: After its region of distribution, forms (Li et al., 2019). namely high-latitude Siberia. Orchard (2007) suggests the derivation of S. Diagnosis: Approximately less than 1 mm long, the griesbachensis (Orchard) from a narrower early pointed and slender unit has a relatively narrow platform. Griesbachian form that represents a P1 morphology The rear edge of the platform is curved down.The platform distinct from the other gondolellid stocks. In a similar bears microreticulae, and on its underside there is a small way to younger genera Borinella and Scythogondolella, oval posterior pit. The conical main cusp is marginal and Siberigondolella appears without a clear root. The late not covered by the rounded edges of the posterior platform. Griesbachian S. griesbachensis and Dienerian S. mongeri Triangular teeth slowly increase in height and width towards are phylogenetically closer to the younger species of the the anterior end and form a low attached blade. genus Siberigondolella (Figure 2). * Correspondence: [email protected] 536

This work is licensed under a Creative Commons Attribution 4.0 International License. KILIÇ and HIRSCH / Turk J Zool

Figure 1. Siberigondolella gen. nov. A–H, W–Z) S. composita (A–H after Dagys, 1984, p. 22, pl. XIV, figs. 1–8; W–Z after Klets and Yadrenkin, 2001, p. 17, pl. 1, figs. 5–6), G is holotype; I–P) S. jakutensis, (after Dagys, 1984, p. 10, pl. I, figs. 10–12, pl. II, figs. 1–5), V) S. cf. jakutensis (after Klets and Yadrenkin, 2001, p. 18, pl. 1, fig. 1); Q–R) S. sibirica (after Dagys, 1984,p. 8, pl. I, figs. 8–9); S–U) S. altera (after Klets and Yadrenkin, 2001, p. 16, pl. 1, figs. 10–11). Approximate scale bar is 500 µm.

While Early Triassic Gondolellidae comprises Late discussed the Smithian appearance of Neogondolella in the Permian-Griesbachian of the subfamily Neodon- context of the Early Olenekian of the northern latitudes dolellinae, in the Latest Griesbachian Siberigondolella of an that yielded endemic Borinella buurensis, B. composita, B. uncertain subfamily appears. Klets and Kopylova (2007) jakutensis, B. taimyrensis, and B. sibirica, all having char-

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Figure 2. Siberigondolella gen. nov. lineage (modified after Orchard, 2007). In the absence of a possible phylogenetic link, the lineage is disconnected from Griesbachian Neogondolellinae. acteristics of Neogondolella in the form of the basal cavity dolella gen. nov. comprises the boreal lineage described as (Dagys, 1984). Specimens of B. buurensis from A. Dagys’s Neogondolella by Dagys (1984) and Klets and Yadrenkin collection were, however, referred by Kozur (1989) to most (2001) (Kilic et al., 2017, p. 350). probably the so-called Neogondolella, evolved from Neo- We suggest here a new genus for a separate lineage of spathodus in the Early Olenekian and widely distributed lanceolate gondolellids mainly described from the Smithi- in southern and northern latitudes. Hirsch (1994) sug- an in Siberia (Dagys, 1984; Klets and Yadrenkin, 2001) and gested the sudden Smithian appearance of Borinella from from the Griesbachian-Dienerian of the Canadian Arctic , branching into a lineage of B. nevadensis-B. (Orchard, 2007): Siberigondolella gen. nov. comprises the jubata and “side” branches of B. nepalensis and S. milleri species S. griesbachensis (Orchard), S. mongeri (Orchard), during a time span that would have left a time gap between S. composita (Dagys), S. altera (Klets), S. jakutensis (Da- the Early Dienerian extinction of Clarkina and the Early gys), and S. sibirica (Dagys). Smithian appearance of Borinella. The genus Siberigon-

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